Tank banding apparatus



Nov. l1,1969 F. X. CROWLEY 3,477,652

TANK BANDING APPARATUS Filed April 17, 1968 FIG. I

INVENTOR. 2 FRANCIS x. CROWLEY United States Patent O 3,477,652 TANK BANDING APPARATUS Francis X. Crowley,- 24 Lanark Road, Wellesley,Mass. 02180 Continuation-impart of 3 application Ser. No. 538,764, Mar. 30, 1966. This application Apr. 17, 1968, Ser.

Int. Cl. B65h 81/06 US. Cl. 242--7.21 1 Claim ABSTRACT OF THE DISCLOSURE This application is filed as a continuation-in-part of my copending application Ser. No. 538,764 filed Mar. 30, 1966, and now abandoned.

This invention comprises new and improved apparatus for controlling the spacing of prestressed reinforcing wire as applied to the wall of an upright tank.

It has been the practice for many years to wrap or bind such tanks with a continuous spiral of wire which maintains the wall of the tank under prestressed compression at all times regardless of variations in internal hydraulic pressure as the tank is filled or emptied. The reinforcing wire is usually covered and protected by an outer cementitious coating and it is important that this should fully cover and protect the reinforcing wire throughout its entire circumference and length. Failure of the cementitious coating to protect is likely to occur if one turn of wire overlaps, crowds or contacts another, and from every standpoint it is desirable to wind the reinforcing wire with a controlled spacing and uniform helical pitch so that the cementitious coating shall completely surround the wire. This can be done only if the wires are spaced a proper distance throughout their entire length. Heretofore the spacing between the turns of the reinforced wire has required the employment of a workman stationed on the ground at the base of the tank who has manipulated the wire guide in accordance with his own best judgment.

An object of the present invention is to provide a wire guide automatically controlled from the ground so that the services of this workman are made unnecessary in constructing the tank and the adjacent turns of the reinforcing wire are spaced with mechanical precision. In its preferred form the apparatus comprises an overhead carriage guided for movement about the upper rim of the tank and having a wire guide suspended from an electrically operated winch on the carriage, together with a wire banding and tensioning vehicle arranged to encircle the base of the tank and having towing connections with the carriage on the tank and also with the suspended wire guide. An electric and calibrated timer is provided in this vehicle having connections with the winch for causing it to lower or raise the wire guide a predetermined distance in selected turns of the reinforcing wire about the tank.

The apparatus of this invention may be advantageously operated to lower or raise the wire guide a measured distance in a predetermined length of the banding wire and thus control and determine the spacing of adjacent turns. For example, in banding a 60 foot diameter tank wall having a circumference of about 188 feet, using a vehicle traveling at 90 feet per minute (approximately one mile an hour), the timer may be set to cause the winch to operate for 15 seconds from a given starting point in the circumstance of the tank. Accordingly 22 feet of the instant turn of wire will be lowered or lifted by operation of the winch, the distance of deflection depending on the gear ratio of the winch, approximately three inches in 15 seconds.

' The timer for this purpose is calibrated for various predetermined spacings of the turns so that one operator at the vehicle may actually dial the number of wires per footlhe wishes to place on the tank wall.

Itwill be apparent that by proper adjustment of timer setting and gear ratio of winch, the vertical deflection of the binding wire may be extended over any desired portion of the turns thereof. This sensitive and direct cont'rol of the binding operation is made possible by the novel arrangement of locating the timer on the traveling vehicle.

The invention will be best understood and appreciated from the following description of a preferred embodiment thereof, selected for purposes of illustration and shown in the accompanying drawings, in which- FIG. 1 is a diagrammatic view showing a tank and one form of apparatus for carrying out my novel process, and

FIG. 2 is a fragmentary view of a developed area of the banded tank wall.

The tank herein shown is cylindrical and may be in the order of 60 feet diameter and 50 feet in height and constructed of reinforced concrete in conventional manner.

An overhead carriage 10 is supported by rollers that are arranged to guide it for movement about the upper rim of the tank when subjected to traction through the medium of a tow line 11 secured to a truck 12 adapted to be driven around and around the base of the tank.

The carriage 10 is provided with a motor driven winch 13 having a reducing gear box 14 and drum from which a wire guide 15 is suspended by a cable 16. The binding wire 17 passes through the wire guide 15 and is controlled in its vertical position on the tank thereby.

The truck 12 is connected to a trailer vehicle 18 whereon are placed coils of banding wire from which the wire is passed through a tensioning die 19 on the wire guide 15 and the tank. The die 19 may be of the character disclosed in United States Letters Patent No. 2,385,796, Oct. 2, 1945, operating to maintain the wire under high uniform tension as it is forcibly drawn through the deforming passage of the die.

The vehicle 18 also carries a come-along device 20 through which extends a tow line 21 to the wire guide 15. By operating this device the tow line 21. may be reeled in and shortened as the wire guide 15 descends along the wall of the tank. The most favorable operating location for the wire guide is slightly in advance circumferentially of the carriage 10. In this position the cable 16 is inclined somewhat from the vertical toward the trailer 18.

The vehicle 18 also carries a timer 22 having electrical connections 23 with the winch of the carriage 10. The timer 22 may be set at the vehicle to run for any selected variable interval of time, stopping automatically when the interval has clasped and so positively controlling the period of which action. Thus, in the present case, the timer may be started opposite a line or point 24 marked on the tank to initiate operation of the winch and will act of its own accord in the example previously given after .22 feet of wire has been wound with controlled deflection.

Further wrapping of the instant turn of wire proceeds without departure from the horizontal. The timer is again started when the vehicle 18 arrives at the point 24, on its next encircling travel about the tank and an equal length 3 of the next turn is wrapped with a deflection parallel to that already established.

While it is generally more convenient to start the wire wrapping operation from the top of the tank and proceed downwardly with the winding it is, of course, within the scope of the invention to wind upwardly or downwardly from any selected starting point on the wall of the tank.

As suggested in FIG. 2, the timer has been started in each revolution of the vehicle 18 at a point opposite the mark 24 on the wall of the tank and has automatically stopped, when the wire has been deflected downwardly to the point 17' as indicated by the dial of the timer.

The timer may be of any commercially available type such, for example, as the Electric Timer D D Y-ll sold by Electric Stop Nut Corporation of America, of Elizabeth, New Jersey. This instrument has a range of 2.5 to 25 sec. and is operated on 12 v. DC current.

While it is usually more convenient to arrange the carriage to run on or above the upper rim of the tank, it would be within the scope of the invention to suspend the carriage against the outer wall and below the upper rim. It is also within the scope of the invention to suspend the wire wrapping and tensioning element between the bottom and top of the wall, in which case traction is derived through connection with a tank-encircling chain or cable.

When the tank is designed for liquid storage the spacing of the wire will be wider about the upper part of the tank wall and closer'or narrower as it approaches the bottom of the wall, in order to compensate for variation of the hydraulic pressure within the tank. For example, in many tanks the top several feet of the tank has 8 turns to the foot, incrementally increasing to 20 turns to the foot at the bottom of the tank wall.

In actual practice the apparatus herein disclosed has the great advantage (1) of binding a tank with same degree of excellence but with a saving of twenty percent in cost as compared with the cost of the same work carried out by other available apparatus; (2) of less apparatus cost, and (3) less danger of mechanical failure as in winding apparatus of the escapement type.

Having thus disclosed my invention what I claim as new and desire to secure by Letters Patent is:

1. Apparatus for banding the wall of an upright tank with prestressed reinforcing wire, comprising an overhead carriage guided for movement about the upper rim of the tank, an electrically operated winch on said overhead carriage, a wire guide suspended from said winch on the carriage, a wire-banding and tensioning vehicle arranged to encircle the wall of the tank, a timer on said movable vehicle within convenient reach from the ground and electrical connections between the timer at the vehicle and said winch on the overhead carriage for causing the winch to move the said wire guide vertically through a predetermined selected and variable distance in selected consecutive turns of the reinforcing wire about the tank wall.

References Cited UNITED STATES PATENTS 2,959,367 11/1960 Kuba et a1. -'71.5 3,128,956 4/1964 Schumann 2427.09 3,167,901 2/ 1965 Stetka 24225 3,281,085 10/1966 Crom 2427.21 3,289,955 12/1966 McBroom et a1. 2427.l1

BILLY S. TAYLOR, Primary Examiner UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,477,652 November 11, 1969 Francis X. Crowley It is certified that error appears in the above identified patent and that said Letters Patent are hereby corrected as shown below:

In the heading to the printed specification, lines 3 to 4, "Francis X. Crowley, 24 Lanark Road, Wellesley, Mass. 02180" should read Francis X. Crowley, Wellesley, Mass. assignor to Crowley-Hession Engineers, Boston, Mass., a partnership Signed and sealed this 4th day of August 1970.

(SEAL) Attest:

WILLIAM E. SCHUYLER, JR.

Commissioner of Patents Edward M. Fletcher, Jr.

Attesting Officer 

